Finding the perfect match between nanoparticles and microfluidics to respond to cancer challenges

The clinical translation of new cancer theranostic has been delayed by inherent cancerâ s heterogeneity. Additionally, this delay has been enhanced by the lack of an appropriate in vitro model, capable to produce accurate data. Nanoparticles and microfluidic devices have been used to obtain new and more efficient strategies to tackle cancer challenges. On one hand, nanoparticles-based therapeutics can be modified to target specific cells, and/or molecules, and/or modified with drugs, releasing them over time. On the other hand, microfluidic devices allow the exhibition of physiologically complex systems, incorporation of controlled flow, and control of the chemical environment. Herein, we review the use of nanoparticles and microfluidic devices to address different cancer challenges, such as detection of CTCs and biomarkers, point-of-care devices for early diagnosis and improvement of therapies. The future perspectives of cancer challenges are also addressed herein.F.R. Maia acknowledges Portuguese Foundation for Scienceand Technology (FCT) for her work contract under theTransitional Rule DL 57/2016 (CTTI-57/18-I3BS5). J. M.Oliveira thanks FCT for his distinction attributed under theFCT Investigator program (IF/01285/2015)

Engineering of extracellular matrix-like biomaterials at nano- and macroscale toward fabrication of hierarchical scaffolds for bone tissue engineering

The increasing rate of musculoskeletal pathologies has compelled the development of improved and novel treatment strategies in order to address unmet clinical needs. Tissue engineering approaches comprising the use of scaffolds for bone regeneration have been showing to be a promising alternative to conventional bone repair/substitution approaches. In particular, hierarchical scaffolds as methods of structural support and osteogenic differentiation promoters are among the most used tools in bone tissue engineering (BTE). In this reasoning, hierarchical scaffolds have sparked the field, striving toward mimicking the natural bone tissue in both, its complex 3D structure and composition. A recent and promising trend has been the merging of nanotechnology and tissue engineering concepts. As such the incorporation of nanoparticles and nanocomposites into micro- or macroscaffold systems can result in an improvement of scaffoldsâ biofunctionality at different levels. These tools are versatile in nature and can be used for multiple purposes such as drug delivery, thermal conductors, and mechanical reinforcement. Taking into consideration multidisciplinary approaches, several strategies have been pursued. The recent reports dealing with the approaches pursued in the hierarchical scaffolds production and enhancement, ranging from the nanoscale to the macroscale, are overviewed herein.The authors thank the funds provided by the project FROnTHERA (NORTE-01-0145-FEDER-000023), supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF), the project 3BioMeD (FCT/4773/ 4/5/2017/S) supported by Fundação para a Ciência e a Tecnologia (FCT) and the R&D Project KOAT PTDC/BTMMAT/29760/2017 (POCI 01-0145-FEDER-029760) financed by FCT and cofinanced by FEDER and POCI. F.R.M. acknowledges FCT for her contract under the Transitional Rule DL 57/2016 (CTTI-57/18-I3BS (5))

Solvency II - An important case in Applied VaR

Value-at-Risk (VaR) is an extremely popular risk measure and many financial companies have successfully used it to manage their risks. Recent developments towards a general single European financial regulation, lead to a great increase in the use of VaR. At least, for European Bank and Insurance industry, VaR is no longer an optional risk management tool, but it became mandatory. In this chapter we focus on the Insurance business and discuss the use of VaR as it has been proposed in the context of the Solvency II (undergoing) negotiations. Our goals are, on the one hand, to present the underlying assumptions of the models that have been proposed in the Quantitative Impact Studies (QIS) and, on the other hand, to suggest alternative VaR implementations, based upon estimation methods and firm specific characteristics. Our suggestions may be used to develop internal models as suggested in Solvency II context. Finally, we analyze the case a of Portuguese insurer operating in the motor branch and compare QIS and internal model VaR implementations. In our concrete application, (one year horizon) capital requirements are similar under the two alternatives, allowing us to conclude for the robustness of the models proposed in QIS.info:eu-repo/semantics/publishedVersio

Investigation of Dendrimer-based nanoparticles cellular uptake and cell tracking in a semiautomated microfluidic platform

A microfluidic device such as Kima Pump and Vena8 biochip is able to realize functions that are not easily imaginable in conventional biological analysis, such as highly parallel, sophisticated high-throughput analysis and single-cell analysis in a well-defined manner [1]. Cancer cell tracking within the microfluidic model will be achieved by grafting fluorescent label probe Fluorescein-5(6)-isothiocyanate (FITC) to dendrimer nanoparticles allowing cell visualization by immunofluorescent staining followed by fluorescence microscopy. In this study, synthesis and physicochemical characterization of Carboxymethyl-chitosan/poly(amidoamine) dendrimer nanoparticles (CMCht/PAMAM NPâ s) were performed[2].  Several cancer cell lines such as a HeLA (cervical carcinoma cell line), HTTC-116 (Colon Carcinoma) and Glioblastome cell line (GBM) were exposed to different concentrations of CMCht/PAMAM dendrimer nanoparticles over a period of 7d. After finding the adequate NP concentration, the internalization efficiency was tested, as well as cellular trafficking, in static and dynamic conditions (Kima Pump bioreactor).Portuguese Foundation for Science and Technology (FCT) through the project PEst­C/SAU/LA0026/20

Glial Cell Line-Derived Neurotrophic Factor-Loaded CMCht/PAMAM Dendrimer Nanoparticles for Peripheral Nerve Repair

(1) Background: Peripheral nerve injuries represent a major clinical challenge. If nerve ends retract, there is no spontaneous regeneration and grafts are required to proximate the nerve ends and give continuity to the nerve. (2) Methods: GDNF-loaded NPs were characterized physicochemically. For that, NPs stability at different pH’s was assessed, and GDNF release was studied through ELISA. In vitro studies are performed with Schwann cells, and the NPs are labeled with fluorescein-5(6)-isothiocyanate for uptake experiments with SH-SY5Y neural cells. (3) Results: GDNF-loaded NPs are stable in physiological conditions, releasing GDNF in a two-step profile, which is beneficial for nerve repair. Cell viability is improved after 1 day of culture, and the uptake is near 99.97% after 3 days of incubation. (4) Conclusions: The present work shows the efficiency of using CMCht/PAMAM NPs as a GDNF-release system to act on peripheral nerve regeneration.This work was supported by the Portuguese Foundation for Science and Technology for the funds provided under the distinction attributed to JMO (IF/01285/2015) and the project NanOptoNerv (ref. PTDC/NAN-MAT/29936/2017). The work was also supported by the European Commission and FEDER program, the JUSTHera project (NORTE-01-0145-FEDER-000055), and the 0624_2IQBIONEURO_6_E project (Inter-regional cooperation program VA Spain-Portugal POCTEP 2014-2020)

Fatty acis profile in Serra da Estrela cheese: an overview

Milk and dairy products are of major importance in the human diet, since they are an excellent source of well-balanced nutrients which are consumed in large amounts and are easy to manufacture. Most cheeses present in the market are made from cow's milk, with ewe’s and goat’s cheeses being considered delicacies derived from the unavailability of goat's and ewe’s milk in certain periods of the year, proleading to a final product with high prices that consumers tend to value given the quality of the final products. Serra Estrela (SE) cheese, a traditional variety manufactured in the center region of Portugal, is part of the national ancient cultural heritage. Made from raw sheep milk it is assumed as an iconic gourmet cheese, when compared with other Portuguese cheeses. In the present work, the evolution of the lipid fraction, namely unsaturated fatty acids such as monounsaturated and polyunsaturated (omega 3 fatty acids and omega 6 fatty acids), was evaluated for a period of 9 months. Chemically it was possible to verify differences in terms of the fatty acid profile between the analysed cheese samples. SE cheese was characterized by a relatively high content of monounsaturated fatty acids (MUFA) and the evaluation of the lipid profile of SE cheese allowed possible future work in determining bioactive lipid compounds with possible health promoting functions.info:eu-repo/semantics/publishedVersio

Magnetically responsive tropoelastin hydrogel as a platform for soft tissue regeneration applications

Publicado em "European Cells and Materials. ISSN 1473-2262. Vol. 33, Suppl. 2, 2017 (0006)"The natural polymer tropoelastin is a structural protein of ECM of tissues requiring elasticity as part of their function, including ligaments and tendons. Tropoelastin has an innate capacity of self-assembly into high-order structures, and together with elastic resilience, structural stability and bioactivity bring forth pleasant singularities in adopting it as a building block to fabricate hydrogels. Moreover, easy tailoring of properties can be attained via incorporation of specific components into the polymeric network, including magnetic nanoparticles (MNPs), which are beneficial for on-demand therapies. Thus, the main goal of this work consisted in developing a magnetically responsive tropoelastin (MagTro) hydrogel as a platform to study the response of tendon cells to a mechanical stimulus induced by application of an external magnetic field (EMF). For this purpose, to first produce hydrogels, a solution of recombinant human tropoelastin was first freeze-dried overnight inside a mould and then chemically cross-linked inside an open desiccator via vapour glutaraldehyde. Thereafter, MagTro hydrogels were obtained through in situ precipitation of MNPs by immersing tropoelastin hydrogels in FeCl2 and FeCl3 solution overnight and secondly by soaking them in NaOH. Hydrogels were then analysed morphologically by Scanning Electron Microscopy (SEM and Cryo-SEM). Enzyme-triggered degradation was studied after 72h at 37oC in a human neutrophil elastase solution. Hydrogels exhibited a quick magnetic responsiveness to an EMF (Fig.1). Interestingly, MagTro hydrogels exhibited smaller pores as observed by Cryo-SEM. This feature can be tuned according to different soft tissue requirements by controlling different parameters of the fabrication process. Additionally, the release of tropoelastin into solution decreased, which suggests the formation of a surface coating of MNPs on tropoelastin network, protecting the hydrogel from a faster degradation. Preliminary results also indicate that cultured cells are viable and spread at the surface of the hydrogel. The application of an EMF to cell-laden MagTro hydrogels will be further investigated. Overall, the streamlined fabrication of MagTro hydrogels was successfully attained and the hydrogel formulation represents a promising potential platform for soft tissue regeneration.The authors acknowledge to BEAM-Master Joint Mobility Project an EU Australian cooperation in Biomedical Engineering Grant Agreement, 2014-1843/001 001-CPT EU-ICI-ECP and to FCT–Fundação para a Ciência e a Tecnologia in the framework of FCT-POPH-FSE, RC-A PhD grant SFRH/BD/96593/2013 and MEG grant IF/00685/2012.info:eu-repo/semantics/publishedVersio

Combining experiments and in silico modeling to infer the role of adhesion and proliferation on the collective dynamics of cells

The collective dynamics of cells on surfaces and interfaces poses technological and theoretical challenges in the study of morphogenesis, tissue engineering, and cancer. Different mechanisms are at play, including, cellâ cell adhesion, cell motility, and proliferation. However, the relative importance of each one is elusive. Here, experiments with a culture of glioblastoma multiforme cells on a substrate are combined with in silico modeling to infer the rate of each mechanism. By parametrizing these rates, the time-dependence of the spatial correlation observed experimentally is reproduced. The obtained results suggest a reduction in cellâ cell adhesion with the density of cells. The reason for such reduction and possible implications for the collective dynamics of cancer cells are discussed.e Portuguese Foundation for Science and Technology (FCT) under Contracts no. PTDC/FIS-MAC/28146/2017 (LISBOA-01-0145-FEDER-028146), UIDB/00618/2020, and UIDP/00618/2020. F.R.M. also acknowledges FCT for her contract under the Transitional Rule DL 57/2016 (CTTI-57/18-I3BS(5)

Consumption of fruits and vegetables in two European countries: Results from a survey in France and Portuga

Presently, there is a huge burden on public health due to a very high incidence of chronic diseases like cardiovascular diseases, diabetes, and obesity, among others. The modern lifestyle, with inadequate diets and insufficient physical activity, is one of the most important factors contributing to this situation. Therefore, a healthy diet can have a very positive impact on global population health. Fruits and vegetables are staple foods with a typically low caloric value that still contribute to an adequate ingestion of the necessary macro and micronutrients and bioactive compounds, with a beneficial effect on health. This study aimed to investigate the knowledge about the consumption of fruits and vegetables in two countries, Portugal and France. A questionnaire survey was carried out on a sample of 639 adult participants (382 French and 257 Portuguese). The results revealed significant differences in knowledge between countries, sexes, level of education, body mass index, satisfaction with body weight, reasons for dissatisfaction with weight, and having a chronic disease. The most influential sociodemographic variable was the country, while the most influential behavioral variable was practicing a varied diet. Factor analysis identified two factors, one accounting for items in the scale that were true, and the other accounting for false items; both factors had acceptable internal consistency. Finally, cluster analysis showed three clusters of participants: The first included individuals with high knowledge of both factors, the second included individuals with low or very low knowledge, and the third cluster included individuals with partial knowledge, who only knew about true items. These results are relevant for planning educational measures aimed at improving knowledge and thus helping to promote healthier diets.info:eu-repo/semantics/publishedVersio

A semiautomated microfluidic platform for real-time investigation of nanoparticles' cellular uptake and cancer cells' tracking

Aims: develop a platform composed of labeled dendrimer nanoparticles and a microfluidic device for real-time monitoring of cancer cells fate. Materials and Methods: The physicochemical and biological characterization of the developed Carboxymethyl-chitosan/poly(amidoamine) (CMCht/PAMAM) dendrimer nanoparticles were performed using TEM, AFM, Zeta Sizer, DSC and cytotoxicity screening. Cancer cell lines derived from different tumor types, including HeLa (Cervical Carcinoma), HCT-116 (Colon Carcinoma) and U87MG (Glioblastoma), were exposed to different concentrations of CMCht/PAMAM dendrimer nanoparticles over a period of 3 days (MTS/DNA). Results: Nanoparticles were successfully modified with an average size of 50 nm. Internalization levels go from 87% to 100% in static and from 95% to 100% in dynamic conditions. Viability levels range from 95% to 100% in static and from 90% to 100% in dynamic conditions, being HCT the most sensitive to the presence of the NP. Conclusions: the results show different responses to the presence of 0.5 mg.mL-1 dendrimer nanoparticles when comparing static to dynamic conditions, with a tendency towards higher sensitivity when subjected to confinement. This work demonstrated that the proposed microfluidic-based platform allows real-time cell monitoring, which, upon more studies, namely the assessment of the drug release effect, could be used for cancer theranostics.FR Maia acknowledges ERC-2012-ADG 20120216–321266 (ComplexiTE) for her Postdoc scholarship. JM Oliveira thanks Portuguese Foundation for Science and Technology (FCT) for his distinction attributed under the FCT Investigator program (IF/00423/2012). BM Costa also thanks Portuguese Foundation for Science and Technology (PTDC/SAU-GMG/113795/2009 and IF/00601/2012 to BM Costa), Fundação Calouste Gulbenkian (BM Costa) and Liga Portuguesa Contra o Cancro (BM Costa). MR Carvalho also thanks the funding through the LA ICVS/3Bs project (UID/Multi/50026/2013). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.info:eu-repo/semantics/publishedVersio